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      08-07-2008, 11:23 AM   #89
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Originally Posted by lucid View Post
I can see preferences coming into play, but a passive setup simply cannot beat a well optimized/programmed active setup. (Larry Koch was kind of rolling his eyes and saying similar things when people asked him about performance differences between the active and passive modes). That's why they banned active suspension in F1 in the 90s.
Maybe with customized optimization for the individual track being run on.F1 had the capabilities to do that
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      08-07-2008, 12:33 PM   #90
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Maybe with customized optimization for the individual track being run on.F1 had the capabilities to do that
Yes, the system would most likely need to be tailored for a specific track for maximum performance, but that doesn't mean that an active setup not tailored for a specific track still can't beat a passive system. Keep in mind that one would need to tune the passive setup for a given track for maximum performance as well.

The issue is that the active system in the M3 might not be optimized to provide maximum performance. I guess we'll never know since we didn't write the code. We don't even know how the system works exactly.

If we put the M3 system aside, I still maintain that an active setup optimized for performance will be faster than any passive setup one can come up with. The system in the M3 is most likely not advanced/complex enough; it is just a mass produced road car. But the systems in the F1 cars were different. If they didn't ban them, we would for sure be seeing significantly faster lap times in F1 today.

Dedicated hardcore control systems can make unstable aircraft not only fly, which is impressive to begin with, but complete complex maneuvers. Make no mistake, a racecar would be no exception. I am not a controls expert, but it seems like member jm1234 is, so you can ask him if you don't take my word for it.
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      08-07-2008, 12:41 PM   #91
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The reason for it being banned in F1 was the unfair advantage it give the human element in a race. The active suspension ironed out the vibrations and bumps much better that the normal setup leaving the driver less drained.

But to compare a sportscar on a race track to an F1 car is apples and oranges, awd was also banned for it's unfair advantage but to say it's better would be to miss the point. Active suspension doesn't feel the same as a well tuned stock suspension, it behaves totally different, I am not saying it's worse or better, just different.
The issue is far beyond "the driver being less drained." The issue is about traction and handling. That's why the F1 cars with active suspension were faster. I don't see why your M3 wouldn't be faster on the track as well if it indeed had active suspension technology F1 cars had.
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      08-07-2008, 01:48 PM   #92
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Quote:
Originally Posted by lucid View Post
The issue is far beyond "the driver being less drained." The issue is about traction and handling. That's why the F1 cars with active suspension were faster. I don't see why your M3 wouldn't be faster on the track as well if it indeed had active suspension technology F1 cars had.

I am not denying the likelihood that EDC will be quicker, my comments were which I would prefer to use on the track, like I have already said I picked EDC for my own road M3 knowing full well that the multi-modes will be very useful in day-to-day driving.

I am also not denying that active suspension may have offered an advantage in traction in the context of F1, I was only commenting on something someone told me about the technology from a driver's perspective, the system produced less fatigue and stress on the driver and a driver who is more relaxed and can see clearly will ultimately be quicker.
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      08-07-2008, 02:31 PM   #93
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I am not denying the likelihood that EDC will be quicker, my comments were which I would prefer to use on the track, like I have already said I picked EDC for my own road M3 knowing full well that the multi-modes will be very useful in day-to-day driving.
Yes, that's why I started my earlier post with "I can see preferences coming into play..."

I guess the jury is still out if BMW really optimized the Normal EDC setting for performance or not. There is a chance they haven't done that--at least not to the extent that it will beat Sport on all tracks. Normal being faster on the Ring might not translate to other tracks. With time, people will gain more experience with both settings and report lap times, and we'll see...
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      08-11-2008, 08:00 PM   #94
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After the past few days of attending 2 different (3 days worth) track events; I must say that I still prefer Sport setting on my EDC than Normal. I have no lap times with data points to analyze my respective times; however by the seat of my pants, sport simply felt quicker in my opinion. Granted, this security I was feeling, may partially be a result of Sport feeling better for "me" at the particular tracks I was at. Other than that, I love MDM, but may soon turn it completely off as it still can be intrusive, and the car's torque is perfect in every gear.

Some pics, enjoy.

http://www.m3post.com/forums/showthread.php?t=162215
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      08-11-2008, 08:24 PM   #95
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Quote:
Originally Posted by footie View Post
I am not denying the likelihood that EDC will be quicker, my comments were which I would prefer to use on the track, like I have already said I picked EDC for my own road M3 knowing full well that the multi-modes will be very useful in day-to-day driving.

I am also not denying that active suspension may have offered an advantage in traction in the context of F1, I was only commenting on something someone told me about the technology from a driver's perspective, the system produced less fatigue and stress on the driver and a driver who is more relaxed and can see clearly will ultimately be quicker.
The real reason that the active suspension cars were brought out was to keep a constant ride height to maximize the aerodynamics so maximum downforce was available even on bumpy tracks.It had nothing to do with driver comfort as the driver is an expendable item in F1 as far as the designers are concerned.It was all about going fast.
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      08-12-2008, 11:07 AM   #96
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Quote:
Originally Posted by Gearhead999s View Post
The real reason that the active suspension cars were brought out was to keep a constant ride height to maximize the aerodynamics so maximum downforce was available even on bumpy tracks.It had nothing to do with driver comfort as the driver is an expendable item in F1 as far as the designers are concerned.It was all about going fast.
If you can control the space between the surface of the road and the underside of the car then you can control the air speed difference between what goes over the car and what goes under it. Active did play a major part in this so I can't disagree with anything you are saying.

I was only commenting on something I was told from one of those expendable items that you talked about. He found the car much softer and ultimately easier to drive, that may have been a by-product of the technology but in his opinion it made a measurable difference as the end of the race approached.
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      08-15-2008, 08:18 PM   #97
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The sport is not the way to go when it is wet,based on my experiance at a wet trackday.See my post here.

http://www.m3post.com/forums/showthr...16#post3170016

Last edited by Gearhead999s; 08-15-2008 at 08:43 PM.
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      08-16-2008, 02:55 AM   #98
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The sport is not the way to go when it is wet,based on my experiance at a wet trackday.See my post here.

http://www.m3post.com/forums/showthr...16#post3170016

no suprize - a soft suspension is usually better in the wet.
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      08-16-2008, 09:23 AM   #99
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no suprize - a soft suspension is usually better in the wet.
True,back in my racing days we would usually disconnect the sway bars to cause more weight transfer to help the grip.I am still suprised by how edgy the car felt with not being able to balance it from turn in to exit.The car is quite quick in the wet with the PS2's on it so maybe with the higher grip level in the wet ,it is much less forgiving than I thought it would be after my experiance in the dry with the 18" Toyo R888's.Still a hell of a lot of fun though!
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      08-16-2008, 11:33 AM   #100
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How does the transfer to oversteer feel comparing, wet vs dry? Does it shift more controllably or is it more inclined to snap free.
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      08-16-2008, 05:30 PM   #101
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How does the transfer to oversteer feel comparing, wet vs dry? Does it shift more controllably or is it more inclined to snap free.

The car felt very different on track in the wet vs the dry with the transfer to oversteer.The previous time I was on my track setup with 18' Toyo R888 255/265 setup and the balance of the car was quite good with the final limit was determined by the rear end and the transition to oversteer was very predictable and quite easy to drive.This time with the factory 19" setup the car was very edgy with the car transitioning from light understeer to a fairly voilent swing to oversteer when the power was employed in the faster(85 mph) 3rd gear corners.In the slower 2nd gear corners it seemed to be spinning up the inside wheel and not bringing the back end out at all but was still accelerating.Very different than the way it was in the dry and nothing like my E46 M3 which you could drive like a drifter in the wet if you wanted to.But despite the feel it was still very quick and still put the power down very well for a sopping track.I was only about 10 seconds behind what my E46 did on R compound tires in the dry on an over 2 minute lap.
I do have lots of experiance in the wet in higher HP RWD cars so I am finding the diff behavour a little bit strange.It is almost like there is a different stratigy used for the wet controlling the diff lockup or maybe the diff is fubared after the noises it was making during my last track day.The dealer changed the diff oil once again so it might be time to do a little investigative work.
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      08-17-2008, 03:29 AM   #102
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Thanks gearhead for the info, I had expected this much and had a theory that it's a lot to do with the EDC. I would like to here what someone has experienced with their M3 on stock suspension.

I could easily be wrong on this one, but I would still like to know.
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      08-17-2008, 09:46 AM   #103
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Thanks gearhead for the info, I had expected this much and had a theory that it's a lot to do with the EDC. I would like to here what someone has experienced with their M3 on stock suspension.

I could easily be wrong on this one, but I would still like to know.
I started the session with the EDC set on the Sport setting which is supposed to be non adaptive and found the car was totaly different in the wet than the way that it felt in dry which I thought was very good if a might bit soft.Going to the softest setting helped the cornering speed and reduced the edgyness somewhat and was quicker but still had the snap oversteer under power.I am almost wondering if some of this caused by the short sidewall on the 19's.I was just thinking that most of my rain running on track was with much higher profile tires in 15,16 & 17" sizes so maybe I am not used to the feel of this setup for the wet.I know that previous track cars did not react this way in the wet and that included my C5 Zo6 which was a blast when it was wet.
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      08-17-2008, 12:43 PM   #104
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Quote:
Originally Posted by Gearhead999s View Post
I started the session with the EDC set on the Sport setting which is supposed to be non adaptive and found the car was totaly different in the wet than the way that it felt in dry which I thought was very good if a might bit soft.Going to the softest setting helped the cornering speed and reduced the edgyness somewhat and was quicker but still had the snap oversteer under power.I am almost wondering if some of this caused by the short sidewall on the 19's.I was just thinking that most of my rain running on track was with much higher profile tires in 15,16 & 17" sizes so maybe I am not used to the feel of this setup for the wet.I know that previous track cars did not react this way in the wet and that included my C5 Zo6 which was a blast when it was wet.
I have debated much on the merits of 18" over 19" and you can't compare a dry lap with 18" against a wet one with 19" and on different tyres. I would like to hear from someone with either 18" or 19" that has stock suspension that has tried their car in both conditions. I'm thinking that it will be a more similar experience in both conditions.

As for using sport on EDC, we all know stiff and wet don't work together and sport is stiffer than stock suspension anyway.

Anyway a higher sidewall will give more and aid cornering in the wet so your experience of higher profile tyres will differ greatly than your 19" M3.
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